World's first LEGO wheelchair

Simon Burfield (aka Burf), made the world's first real live size wheelchair, that can support up to 90 Kg!
Simon, known for building BIG robots was at AFOLCON in Manchester, where he met Eric, who's also known for building massive models. the two got a drink and they decided to make a bet:

Who would be the first person to make a vehicle that could carry 120 pounds.(60 KG)?